Ancient DNA Links Native Americans With Europe – “…from the complete nuclear genome of a Siberian boy who died 24,000 years ago — the oldest complete genome of a modern human sequenced to date. His DNA shows close ties to those of today’s Native Americans. Yet he apparently descended not from East Asians, but from people who had lived in Europe or western Asia. The finding suggests that about a third of the ancestry of today’s Native Americans can be traced to ‘western Eurasia,’ with the other two-thirds coming from eastern Asia…. It also implies that traces of European ancestry previously detected in modern Native Americans do not come solely from mixing with European colonists, as most scientists had assumed, but have much deeper roots.” — see also: The First of the Mohicans from greg cochran.

Your face may have been sculpted by junk DNA – “There is a huge degree of variation in human faces but, as family resemblances show, the overall shape is heavily constrained by genetics. However, so far, geneticists have identified only a small number of genes that influence the shape. These explain just a tiny fraction of the variation seen in human faces. According to Axel Visel of the Lawrence Berkeley National Laboratory in California and his colleagues, more variation is controlled by distant-acting enhancers. These are short sequences of DNA, in non-coding regions of the genome, that can influence the activity of the facial genes, even if they are a long way along the DNA strand.”

Behavior problems in preschool and child care centers may be an issue of genes – “A new study suggests that some children may be genetically predisposed to developing behavioral problems in child care and preschool settings…. [B]irth parents who had high rates of negative emotion and self-control, based on a self-reported temperament scale, were more likely to have children who struggled with behavioral issues such as lack of self-control and anger, in child care centers. They controlled for adoptive parent’s characteristics, and still found a modest effect based on the genetic link.”

Your Ethnicity Determines the Species of Bacteria That Live in Your Mouth – “[P]eople from each of the four different ethnic groups represented in the study (all participants self-identified as either Caucasian, African-American, Chinese or Latino) generally had similar species of bacteria, especially underneath the gums. As a result, simply by counting which varieties of bacteria appeared in this area, the researchers developed a model that was able to guess a person’s ethnicity with an accuracy significantly better than chance — it got it right 62 percent of the time. Some groups were even easier to identify via the bacteria than others: It could correctly identify Latinos 67 percent of the time and African-Americans with 100 accuracy. The variation along ethnic lines, they believe, is a reflection of genetics, not environment. That’s because, if you assumed that the mouth microbiome is totally dependent on environmental factors, you’d expect that members of the same ethnic group would have different mixes of bacteria depending on whether they were first-generation immigrants to the U.S. or had family histories that stretched back generations in the country. Instead, people’s background — in terms of foods they ate and other lifestyle trends — didn’t seem to have any correlation with the bacterial communities in their mouths.“ – h/t super bob!

Herpes virus genome traces the ancient path of human migration – “Researchers…sequenced the genomes of 31 samples of herpes simplex virus type-1 to reconstruct how it hitchhiked on humans as they dispersed around the world. The results match the pattern proposed by the ‘Out of Africa’ theory, which has become the most widely accepted scenario for ancient human migration. The analysis showed that African strains of the virus contained the most genetic diversity — suggesting that they had the oldest roots.”

Life on Earth Was Not a Fluke – “Figuring out how biomolecular self-organization happens may hold the key to understanding life on Earth formed and perhaps how it might form on other planets.” – h/t jayman!

Low historical rates of cuckoldry in a Western European human population traced by Y-chromosome and genealogical data – “[W]e estimate that over the last few centuries, EPP rates in Flanders (Belgium) were only around 1–2% per generation. This figure is substantially lower than the 8–30% per generation reported in some behavioural studies on historical EPP rates, but comparable with the rates reported by other genetic studies of contemporary Western European populations. These results suggest that human EPP rates have not changed substantially during the last 400 years in Flanders and imply that legal genealogies rarely differ from the biological ones.” – h/t rob brooks!

Sex on the Mind – “It is a truth universally acknowledged — at least by biologists — that every person owes his or her existence to parents who successfully reproduced, each of whom, in turn, had two parents who did the same … and so on, going back hundreds of millions of years to the first ancestral blob (or two) of protoplasmic goo that trundled onto terra firma from the early earth’s organic soup.” – from david barash. — see also: Why Have Sex? – from the advanced apes.

Asymmetries in altruistic behavior during violent intergroup conflict – “Some empirical studies on intergroup conflict in hunter-gatherer societies and chimpanzees indicate that fitness relevant risks and potential benefits of attacks and defenses might have differed substantially under ancestral conditions. Drawing on these studies, it is hypothesized that the success of defenses was much more important for individual and kin survival and that a disposition to act altruistically during intergroup conflict is thus more likely to evolve for the strategic situation of defense…. Analyzing detailed historical case data from 20th century wars, this study finds that altruistic behavior towards members of the in-group indeed seems to occur more frequently when soldiers are defending themselves and their comrades against enemy attacks.” – h/t hbd bibliography!

Paradoxes of the Nordic Model II – “Denmark is a high trust, highly cooperative society. There is very low crime. Most parked bicycles are not even locked. Bank employees may not work very efficiently, but nobody tried to swindle me. In theoretical terms, what it means is that when there are very few defectors, the amount of common good produced overall is maximized. So everybody is well of, even though they don’t work hard – but they don’t free-ride, either….” – from peter turchin.

Napoleon Chagnon: The Fierce Sociobiologist – “[Yanomamo] Men from the highland villages were much less belligerent than men from villages along the river. Heterogeneity in belligerence existed even within this single tribe.”

bonus bonus bonus bonus: The couple having four babies by two surrogates – “A British couple are to become parents of two sets of twin babies carried by two Indian surrogate women they have never met. Experts say twiblings – or children born to separate surrogates but created from the same batch of embryos – are not uncommon in India.”

bonus bonus bonus bonus bonus: Gang Rape in India, Routine and Invisible – “[T]he Mumbai case provides an unusual glimpse into a group of bored young men who had committed the same crime often enough to develop a routine. The police say the men had committed at least five rapes in the same spot. Their casual confidence reinforces the notion that rape has been a largely invisible crime here, where convictions are infrequent and victims silently go away.” – see also: Trying to Make Sense of India’s Sexual Violence, State by State from t.greer.